In commercial container filling or packaging operations, the containers typically are moved by a conveying system at very high rates of speed. Typically, a concentrated lubricant is diluted with water to form an aqueous dilute lubricant solution (i.e., dilution ratios of 100:1 to 500:1), and copious amounts of aqueous dilute lubricant solutions are typically applied to the conveyor or containers using spray or pumping equipment. These lubricant solutions permit high-speed operation of the conveyor and limit marring of the containers or labels, but also have some disadvantages. First, dilute aqueous lubricants typically require use of large amounts of water on the conveying line, which must then be disposed of or recycled, and which causes an unduly wet environment near the conveyor line. Second, some aqueous lubricants can promote the growth of microbes. Third, by requiring dilution of the concentrated lubricant dilution errors can occur, leading to variations and errors in concentration of the aqueous dilute lubricant solution. Finally, by requiring water from the plant, variations in the water can have negative side effects on the dilute lubrication solution. For example, alkalinity in the water can lead to environmental stress cracking in PET bottles.
When an aqueous dilute lubricant solution is used, it is typically applied at least half of the time the conveyor is running, and usually it is applied continuously. By running the aqueous dilute lubricant solution continuously, more lubricant is used than is necessary, and the lubricant concentrate drums have to be switched out more often than necessary.
“Dry lubes” have been described in the past as a solution to the disadvantages of dilute aqueous lubricants. A “dry lube” historically has referred to a lubricant composition with less than 50% water that was applied to a container or conveyor without dilution. However, this application typically required special dispensing equipment and nozzles and energized nozzles in particular. Energized nozzles refer to nozzles where the lubricant stream is broken into a spray of fine droplets by the use of energy, which may include high pressures, compressed air, or sonication to deliver the lubricant. Silicone materials have been the most popular “dry lube”. However, silicone is primarily effective at lubricating plastics such as PET bottles, and has been observed to be less effective at lubricating on glass or metal containers, particularly on a metal surface. If a plant is running more than one type of container on a line, the conveyor lubricant will have to be switched before the new type of container can be run. Alternatively, if a plant is running different types of containers on different lines, the plant will have to stock more than one type of conveyor lubricant. Both scenarios are time consuming and inefficient for the plant.
It is against this background that the present invention has been made.